Continuous nasal positive airway pressure or continuous positive airway pressure (“CPAP”) has been used to treat a variety of diseases including sleep apnea. Most devices used to treat sleep apnea are expensive, cumbersome and designed for repeat use; therefore, they are not used in the operating room, emergency room, or critical care areas. During sedative anesthesia using nasal cannula to deliver oxygen, it is not uncommon for the patient's airway to obstruct as in sleep apnea and for the patient to become hypoxic. This is more marked during procedures in which the upper airway is shared with the surgeon or endoscopist. Various maneuvers such as delivering high oxygen flow rates or jaw thrusts have been used to overcome the obstruction with varying success. Occasionally, endotracheal intubation or canceling and postponing the procedure are necessary.
What is needed in the industry is a nasal cannula that can be contoured to each patients face, providing nasal inserts that are long enough to rest inside the patients nares, flared at the ends to provide a loose seal and covering the tubing and nasal facial area with a transparent dressing, enabling nasal CPAP to be obtained, improving oxygenation. Such a device would overcome the inherent problem of existing nasal cannulae, which are designed to loosely fit in the nares and cannot easily contour to the face making it difficult to provide a seal and nasal CPAP.
A number of inventions have been proposed to allow contouring or adhering the cannula to the upper lip, widening the nasal inserts to provide a complete seal for providing CPAP or just securing the nasal cannula by an adherent dressing. None of these approaches has solved the problems—discussed.
U.S. Pat. No. 3,513,844 issued on May 26, 1970 to Smith describes a nasal cannula having a metal insert between the nostril conduits to permit manual shaping and contouring to the upper lip. The metal insert is attached to the outside of the cannula and is not incorporated into the bridge. Unlike the present invention where it is necessary for the bridge to extend beyond the upper lip to both cheek areas to provide as much of an airtight fit as possible, the Smith cannula bridge does not extend beyond the upper lip.
U.S. Pat. No. 4,278,082 issued on Jul. 14, 1981 to Blackmer describes a nasal cannula where the two-formed ends of the cannula are attached to a metal bridge, which spans the distance between the narine tubes and may be shaped to provide a more comfortable fit.
U.S. Pat. No. 5,513,635 issued on May 7, 1996 to Bedi describes an adhesive dressing applied to the nose with extensions that wrap around the cannula. The purpose is to secure the cannula to the nose without covering the nostrils.
U.S. Pat. No. 5,682,881 issued on Nov. 4, 1997 to Winthrop et al describes a nasal cannula CPAP device which uses adhesive foam strips attached to the outside of the body of the cannula to secure it to the upper lip to hold it in position under the nose.
Nasal CPAP devices with various means to completely seal the nares have been described in U.S. Pat. Nos. 4,648,498, 5,269,296, 6,431,172, 7,047,974, and 7,188,624. These patents use various materials and shapes such as silicone, foam or inflatable cushions all with the intent to seal the nares to provide CPAP. Use of these approaches have been shown to irritate or otherwise damage the inside of the nares. The present invention does not use an approach wherein the cannula completely seals the nares.
Tse et al describe the use of a clear plastic sheet placed over the face of a patient and taped to their head during upper endoscopy and other sedative procedures. The nasal cannula effectively becomes a face tent providing an oxygen reservoir increasing the inspired oxygen concentration and patient oxygenation. Unfortunately, this is somewhat cumbersome to apply, may be anxiety provoking and may impede the performing the operative procedure. This approach also does not lend itself to use in the emergency room or other critical areas.
In contrast to other nasal CPAP devices, embodiments of this invention employ unique approaches to seal the nostrils to create positive nasal airway pressure to overcome upper airway obstruction while being easily and quickly applied to the patient, economical, disposable, and would be available for use in a wide variety of settings.
What is needed in the industry is a device to provide CPAP comprising soft ovoid nasal inserts covering the end of the delivery tubes designed not to completely seal the nostrils, but to partially seal them. This decreases nasal mucosa irritation, facilitates patient comfort and acceptance, and increases ease of insertion and removal of the cannula while still decreasing the amount of entrained room air.
What is needed in the industry is a device to provide CPAP comprising a cannula softly encasing a malleable metal or plastic bar inside the bridge of the nasal cannula that extends to contour to both sides of the face. This allows the bridge of the nasal cannula to contour to the area of the face at the upper lip and continuing to the side of the nose. The nasal inserts may be angled slightly outward to allow contouring to a variety of anatomies when the semi rigid metal bar is shaped to the face.
What is needed in the industry is a device to provide CPAP comprising an anatomically shaped op site or Tegaderm dressing shaped to fit the nose and upper lip and areas just to the sides of the nose. This provides a complete seal to the nares to provide nasal CPAP.
What is needed in the industry is a device to provide CPAP comprising an option so that the design of the end of the cannula can be fit inside a special nasal airway. This could be useful during longer surgeries where access to the airway may be impeded and where a patient with a difficult airway may require sedation for several hours.
Embodiments of the present invention overcome one or more of these limitations of known devices by creating a novel and non-obvious nasal cannula that can be contoured to each patients face, providing nasal inserts that are long enough to rest inside the patients nares, and in one embodiment, flared at the ends to provide a loose seal, and covering the tubing and nasal facial area with a transparent dressing, to permit nasal CPAP to be obtained and improving oxygenation. This overcomes the inherent problems of existing nasal cannulae, which are designed to loosely fit in the nares and cannot easily contour to the face making it difficult to provide a seal and nasal CPAP or fit tightly in the nares, thereby irritating the nasal mucosa.
Embodiments of the present invention are designed to overcome one or more of the limitations of currently known devices. These, as well as other objects and advantages of the present invention will be better understood from the detailed description and accompanying drawings.